/*
 * RED5 Open Source Flash Server - http://code.google.com/p/red5/
 * 
 * Copyright 2006-2014 by respective authors (see below). All rights reserved.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.red5.server.service;

import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.util.HashSet;
import java.util.Set;

import org.red5.server.api.service.IPendingServiceCall;
import org.red5.server.api.service.IPendingServiceCallback;

/**
 * Pending call is remote call operation that is in pending state. Remote calls to services
 * are asynchronous, that is, after call but before result callback remote calls are in
 * pending state.
 */
public class PendingCall extends Call implements IPendingServiceCall {

	private static final long serialVersionUID = 3219267601240355335L;

	/**
	 * Result object
	 */
	private Object result;

	/**
	 * List of callbacks (event listeners)
	 */
	private HashSet<IPendingServiceCallback> callbacks = new HashSet<IPendingServiceCallback>();

	public PendingCall() {
	}

	/**
	 * Creates pending call with given method name
	 * @param method    Method name
	 */
	public PendingCall(String method) {
		super(method);
	}

	/**
	 * Creates pending call with given method name and array of parameters
	 * @param method    Method name
	 * @param args      Parameters
	 */
	public PendingCall(String method, Object[] args) {
		super(method, args);
	}

	/**
	 * Creates pending call with given method name, service name and array of parameters
	 *
	 * @param name      Service name
	 * @param method    Method name
	 * @param args      Parameters
	 */
	public PendingCall(String name, String method, Object[] args) {
		super(name, method, args);
	}

	/** {@inheritDoc}
	 */
	public Object getResult() {
		return result;
	}

	/** {@inheritDoc}
	 */
	public void setResult(Object result) {
		this.result = result;
		setStatus(result == null ? STATUS_SUCCESS_NULL : STATUS_SUCCESS_RESULT);
	}

	/** {@inheritDoc} */
	public void registerCallback(IPendingServiceCallback callback) {
		callbacks.add(callback);
	}

	/** {@inheritDoc} */
	public void unregisterCallback(IPendingServiceCallback callback) {
		callbacks.remove(callback);
	}

	/** {@inheritDoc} */
	public Set<IPendingServiceCallback> getCallbacks() {
		return callbacks;
	}

	@Override
	public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
		super.readExternal(in);
		result = in.readObject();
	}

	@Override
	public void writeExternal(ObjectOutput out) throws IOException {
		super.writeExternal(out);
		out.writeObject(result);
	}
}
